This invention relates to electromagnetic contactors and more particularly to small, low cost electromagnetic contactors of the type used in air conditioning and heating systems.
Small low cost electromagnetic contactors of the type disclosed in the Moran et al U.S. Pat. No. 3,014,103 issued Dec. 19, 1961, and the Woods U.S. Pat. No. 3,243,546 issued Mar. 29, 1966, and the Woods U.S. Pat. No. 4,199,740 issued Apr. 22, 1980 are commonly employed in air conditioning and heating systems. In such contactors, the switch terminal and contact structure is carried by a terminal and contact block mounted in cantilever fashion on one leg of a L-shaped magnetic frame. Because the blocks of such contactors are supported at only one location, they have sometimes been deflected or damaged in use, especially when external connectors are attached to the switch terminal and contact structure.
In contactors such as those disclosed in the above cited patents, the coil terminals extend radially of the coil assembly between the ends thereof at positions remote from the switch and contact structure and are not readily accessible from the top of the contactor where the switch terminals are disposed. Applying and removing the external coil connectors therefore may be cumbersome or difficult when such contactors are installed in air conditioning and heating systems. Furthermore, the connections between the coil terminals and the coil are sometimes damaged when the external connectors are improperly applied or removed.
In the Obszarny U.S. Pat. No. 3,209,095 issued Sept. 28, 1965, there is disclosed a somewhat similar type of contactor with the coil terminals disposed in recessed arms extending outwardly from one end flange of a coil bobbin. A pair of posts on the terminal and contact block of this contactor supports the bobbin arms and are hollow to receive screws for making electrical connections to the coil terminals from the opposite side of the block. Although the coil terminals are supported to prevent their being damaged and are accessible from either side of the block for screw connections to external connectors, this arrangement is somewhat cumbersome in use.
The Bruce U.S. Pat. No. 3,359,395 issued Dec. 19, 1967 discloses another arrangement for attaching coil terminals to the flange of bobbin. Terminals provided with a pair of lugs are inserted in cross-shaped recesses with the lugs extending through suitable openings and bent toward one another to secure the terminals from movement. This particular terminal arrangement is adapted to a reed relay intended for use with a printed circuit board and is not especially suited for use with the coil assembly of an electromagnetic contactor.